RESUMO
T cell infiltration and proliferation in tumor tissues are the main factors that significantly affect the therapeutic outcomes of cancer immunotherapy. Emerging evidence has shown that interferon-gamma (IFNγ) could enhance CXCL9 secretion from macrophages to recruit T cells, but Siglec15 expressed on TAMs can attenuate T cell proliferation. Therefore, targeted regulation of macrophage function could be a promising strategy to enhance cancer immunotherapy via concurrently promoting the infiltration and proliferation of T cells in tumor tissues. We herein developed reduction-responsive nanoparticles (NPs) made with poly (disulfide amide) (PDSA) and lipid-poly (ethylene glycol) (lipid-PEG) for systemic delivery of Siglec15 siRNA (siSiglec15) and IFNγ for enhanced cancer immunotherapy. After intravenous administration, these cargo-loaded could highly accumulate in the tumor tissues and be efficiently internalized by tumor-associated macrophages (TAMs). With the highly concentrated glutathione (GSH) in the cytoplasm to destroy the nanostructure, the loaded IFNγ and siSiglec15 could be rapidly released, which could respectively repolarize macrophage phenotype to enhance CXCL9 secretion for T cell infiltration and silence Siglec15 expression to promote T cell proliferation, leading to significant inhibition of hepatocellular carcinoma (HCC) growth when combining with the immune checkpoint inhibitor. The strategy developed herein could be used as an effective tool to enhance cancer immunotherapy.
RESUMO
Objective@#To examine the dose-response association between cardiorespiratory fitness ( CRF ) and the risk of cardiovascular and cerebrovascular diseases.@*Methods@#A joint search was performed in Chinese and English electronic databases, including China National Knowledge Infrastructure ( CNKI ) , Wanfang Data, VIP, CBM, PubMed, Embase and Web of Science, to retrieve publications reporting the correlation between CRF and the risk of cardiovascular and cerebrovascular diseases until May, 2021. The pooled risk was estimated using the random effects model, and the dose-response association was evaluated using restricted cubic splines. The source of heterogeneity was assessed by subgroup analysis, and the stability of the results was tested by the trim-and-fill method, while the publication bias was assessed using funnel plots.@*Results@#Totally 37 280 literatures were identified, and 23 eligible studies were finally included in the analysis, which covered 2 605 622 subjects. There were 22 publications identified as high-quality. Meta-analysis revealed that the pooled risk of cardiovascular and cerebrovascular diseases reduced by 42% in the highest CRF group relative to the lowest CRF group ( OR=0.58, 95%CI: 0.52-0.65 ), and a one metabolic equivalent ( MET ) increase in CRF caused a 10% reduction in the pooled risk of cardiovascular and cerebrovascular diseases ( OR=0.90, 95%CI: 0.88-0.92 ). There was a negative linear correlation between CRF and the incidence of cardiovascular and cerebrovascular diseases ( P=0.396 ). Subgroup analysis identified gender, sample size and study regions as possible sources of heterogeneity, and sensitivity analysis showed that the study results were stable.@*Conclusions@#There is a negative linear correlation between CRF and the risk of cardiovascular and cerebrovascular diseases, and an increase in CRF may reduce the risk of cardiovascular and cerebrovascular diseases.